1. Field of the Invention
The present invention relates to casings suitable for containing products that are to be packed individually, and more particularly to casings that comprise a tube ruffled to form the shape of a “caterpillar” or an accordion. The present invention further relates to methods for preparing casings as well as to their use in food and other products.
2. Description of Related Art
Casings are generally disclosed in EP-B 0 799 571 [“EP '571”]. The casings described in EP '571 are packed and transported in a special container that is designed as a transport and moistening container with a water inlet and outlet. The casings are wetted in the container at the client's premises before they are filled in order to provide the casings with the flexibility needed for the filling process.
In the field of ruffled, unstuffed casings, small caliber sausage casings (i.e., those with a diameter of less than about 85 mm) are generally known. Such casings are used for many types of products such as smoked sausage. In conventional processes for stuffing such casings, it is possible to employ known types of stuffing machines. The stretched, flat casings, which are bound off at one end, and generally have a length of 100 to 180 cm, for example. When such casings are stuffed, they are first softened in water to render them pliable. The softened casings are then drawn or fitted by hand onto a filling spout and ruffled. As such, the operator must invariably perform repetitive ruffling motions by hand, which is very tiring. Casings having lengths of more than about 1.80 meters are generally completely shapeless and formless. As such, it is difficult if not impossible to draw such long casings onto the stuffing spout in the time allotted by the machine's operating cycle. The result is that the casing will clutch the filling spout tightly, such that it cannot be ruffled manually.
DE-A 43 14 949 discloses a ruffled casing for single products, which is compactly packaged, so that ruffling the casing prior to stuffing it is not needed. The ruffled casing is compactly packaged and can be held in the hand of the person operating a stuffing machine and drawn onto the spout without the need to manually ruffle the casing by hand. Before ruffling, the casing has a length of 1.02 to 1.52 meters and is not longer than about 1.78 meters.
In another known process, which is also mentioned in DE-A 43 14 949 and which refers to Section III of the publication, “Sausage Casing Technology,” edited by Indel Karmas and published by Noyes Data Corporation, New Jersey (1974), great lengths of casing are ruffled in caterpillar-like (or accordion-like) strands or ropes. The ruffled strands contain about 20 meters of casing-that has been ruffled or collapsed to a length of about 35 to 44 centimeters. The strand is wrapped in a mesh that prevents it from becoming unruffled. The inclusion of the mesh makes it possible for the casing to be softened in water in a ruffled condition so as to attain flexibility and elasticity. After softening, the wrapping is removed and the casing is drawn onto the stuffing spout. In comparison to single casings, the inclusion of strands generally requires the use of a more complicated or complex machine, since when ruffled strands of casing are employed, the casing must be double-clasped, cut and laid in loops, and also as filled with sausage or other product. Since the strand has a far greater length than usual, twenty (20) to fifty (50) sausages can be made from one strand with a machine such as that disclosed in the above-mentioned publication.
In the process described above, manual ruffling of the casing is not required. However, processes employing long ruffled strands can also be disadvantageous, for example, because the stuffing spout for long strands must have a smaller diameter than the that required for stuffing spouts used with single casings. For example, when preparing casings for a sausage with a diameter of 50 mm from long strands, a stuffing spout with a diameter of 28 millimeters or less and a length from 600 to 1000 mm can be used; in comparison, a thicker stuffing spout with a diameter of 36 mm and a length of 500 mm, for example, can be used to prepare individual casings having the same diameter (50 mm). To compress very long casing material to a length capable of being handled by the stuffing machine, a ruffling mandrel of a small diameter must generally be used. Problems associated with using casings having small inner diameters are intensified when the strands are softened in water before stuffing. While it is softening, the strand swells, resulting in a further narrowing of its inner diameter such that an even smaller stuffing spout is necessary. The use of a longer stuffing spout with a smaller diameter results in a slower throughput, increased smearing of fat and poorer particle determination.
Since nowadays casings are generally composted after they are used, an effort is often made to enable casings with a length greater than 1.50 meters to be ruffled without additional mesh material, since the material used for the mesh is generally not very compostable or degradable.
With respect to the casings disclosed in EP-B 0 799 571, it remains the prevailing opinion that when casings are wetted before they are tied off, it is impossible to achieve perfect pleating or to achieve secure and lasting closure of the end of the casing. Furthermore, casings such as those of EP '571 must be soaked for a long time before they are ready for stuffing, and a large unit is required to contain the packing case and the soaking tank during transportation.